Oak, Ivy, Sumac - Oh My!
Here’s how to recognize, avoid and treat contact with Toxicodendron Diversiloba (Poison Oak), T. Radicans (Poison Ivy) and T. Vernix (Poison Sumac).
Often called the "great mimics," Poison Ivy and Oak have a harmless appearance. They are difficult to distinguish from other plants, because they tend to adopt the growth pattern of the plants that surround them. If they take root among tall shrubs, they will grow as tall shrubs. If their home is a field with no tall growth nearby, they grow as a short, innocent-looking weed.
Poison Oak and Poison Ivy - Leaves of Three
These two plants always appears nondescript, making victims
wonder what exactly gave them the itchy rash a day or two later. With either
species, there is one reliable truism: "Leaflets Three, Let It Be." Poison Oak
and Ivy ALWAYS grow their leaves in groups of three. It doesn’t matter if the
leaves look like ivy leaves, oak leaves or have a simple oval shape.
Look for the pattern of three leaflets branching from a single, independent
stem. You’ll find two leaves attached directly to the stalk, opposite each
other. The third leaf will jut from between them on a short stem, forming a
distinct T pattern. In dry weather the leaves may droop, making the pattern hard
to identify.
The second clue to identifying the Toxicodendron Trio is that their leaves tend to have a dull gloss, especially in the Spring when the foliage is new. This sheen is the toxic oil that coats all parts of the plant: Urushiol (pronounced you-ROO-she-all). If the plant is growing in a dusty area, the sheen will be less obvious. The toxic oil is not affected.
Upon contact with any of these three plants, the oil binds to your skin. The first time this happens, your body recognizes this "attack" and prepares an immune response. You seldom have a reaction to your first contact, but your immune system certainly does.
For your second encounter, your immune system is poised to launch a severe allergic reaction. When you brush against one of these nuisances again, the Urushiol oil triggers a powerful reaction. Like a mosquito bite, but 1,000 times worse, your immune system tries to eliminate the areas of your skin that made contact with the plant. Those areas of your skin begin to itch like mad. Scratching the itch only makes it worse, because scratching increases your immune response, and can spread the Urushiol to unaffected areas.
At this point, you have a couple weeks of misery ahead of you, as your body gradually sheds the "contaminated" skin, and the allergic reaction runs its course. Calamine Lotion and anti-itch potions can help here. They help the healing process by numbing the itch reflex, and by providing a coating to your skin that supports the healing process.
Preventing Poison Oak, Ivy, or Sumac Rash by Washing
If you know that you rubbed against one of these plants, wash the affected area immediately with plenty of soap and water. You’ll also need to wash anything you were wearing at the time. If you went to bed before you realized you had a problem, wash the sheets, your pajamas and anything else you wore afterward. Wash the dog too, if it went bounding off into strange shrubbery.